DE3141707A1 - Apparatus for producing heat in a pressure fluid, in particular for heating a closed space - Google Patents

Apparatus for producing heat in a pressure fluid, in particular for heating a closed space

Info

Publication number
DE3141707A1
DE3141707A1 DE19813141707 DE3141707A DE3141707A1 DE 3141707 A1 DE3141707 A1 DE 3141707A1 DE 19813141707 DE19813141707 DE 19813141707 DE 3141707 A DE3141707 A DE 3141707A DE 3141707 A1 DE3141707 A1 DE 3141707A1
Authority
DE
Germany
Prior art keywords
pressure
line
pressure valve
valve
heating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
DE19813141707
Other languages
German (de)
Other versions
DE3141707C2 (en
Inventor
Herbert 5201 Winterscheid Beuermann
Werner 8773 Frammersbach Gitter
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bosch Rexroth AG
Original Assignee
Mannesmann Rexroth AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mannesmann Rexroth AG filed Critical Mannesmann Rexroth AG
Priority to DE19813141707 priority Critical patent/DE3141707A1/en
Publication of DE3141707A1 publication Critical patent/DE3141707A1/en
Application granted granted Critical
Publication of DE3141707C2 publication Critical patent/DE3141707C2/de
Granted legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0427—Heating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/047—Preventing foaming, churning or cavitation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30505—Non-return valves, i.e. check valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means
    • F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
    • F15B2211/50518—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using pressure relief valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5157—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a pressure source and a return line
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/61—Secondary circuits
    • F15B2211/611—Diverting circuits, e.g. for cooling or filtering
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/62—Cooling or heating means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/85—Control during special operating conditions
    • F15B2211/851—Control during special operating conditions during starting

Abstract

An apparatus for producing heat in a pressure fluid, in particular for heating a closed space allocated to a drive unit, has a pump (2) and a pressure valve (23) as heat-producing members, through which the pressure fluid can flow, as well as a heat exchanger (20). In order to largely prevent foaming of the fluid pressure medium, a restrictor (24) is arranged downstream of the pressure valve. <IMAGE>

Description

"Vorrichtung zum Erzeugen von Wärme in einer Druckflüssigkeit"Device for generating heat in a pressure fluid

insbesondere zum Beheizen eines geschlossenen Raumes" Die Erfindung bezieht sich auf eine Vorrichtung entsprechend dem Oberbegriff des Anspruches 1.especially for heating an enclosed space "The invention relates to a device according to the preamble of claim 1.

Der vorliegenden Erfindung liegt die Aufgabe zugrunde, ein Schäumen des flüssigen Druckmittels weitgehend zu verhindern.The present invention is based on the object of foaming to largely prevent the liquid pressure medium.

Diese Aufgabe wird durch die Merkmale im kennzeichnenden Teil des Anspruches 1 erfindungsgemäß gelöst. Die Anordnung der Drosselstelle hat den Vorteil, daß das flüssige Druckmittel nach Verlassen des Druckbegrenzungsventils nicht sofort auf Atmosphärendruck sondern auf einen Zwischendruck entspannt wird. Erst nach Durchtritt des flüssigen Druckmittels durch die Drosselstelle wird dieses auf Atmosphärendruck weiter entspannt. Die nachgeschaltete Drosselstelle bewirkt eine zweistufige Entspannung des Druckmittels.This task is made possible by the characteristics in the characterizing part of the Claim 1 solved according to the invention. The arrangement of the throttle point has the advantage that the liquid pressure medium does not immediately after leaving the pressure relief valve is relaxed to atmospheric pressure but to an intermediate pressure. Only after passing through of the liquid pressure medium through the throttle point, this is at atmospheric pressure further relaxed. The downstream throttle causes a two-stage relaxation of the pressure medium.

Die zum Druckventil parallel geschaltete Drosselstelle nach Anspruch 2 ermöglicht einen drucklosen Anlauf der Punpe. Da ein Hochfahren der Pumpe unter Druck vermieden wird, wird die Pumpe auf ihrer Druckseite wirksam entlüftet.The throttle point connected in parallel to the pressure valve according to claim 2 enables the pump to start up without pressure. As a start up of the pump under Pressure is avoided, the pump is effectively vented on its pressure side.

Weitere Vorteile ergeben sich aus der Beschreibung und der Zeichnung. In dieser ist ein Schaltbild einer Vorrichtung zum Erzeugen von Wärme in einer Druckflüssigkeit zum Beheizen eines einer Antriebseinheit zugeordneten geschlossenen Raumes als Auführungsbeispiel des Gegenstandes der Erfindung schematisch dargestellt.Further advantages emerge from the description and the drawing. In this is a circuit diagram of a device for generating heat in a pressure fluid for heating a closed space assigned to a drive unit as an example of the subject matter of the invention shown schematically.

An eine Ölwanne 1 einer nicht dargestellten Antriebs einheit ist eine Pumpe 2 mit ihrer Saugleitung 3 angeschlossen. Eine Druckleitung 4 der Pumpe 2 ist mit einem Anschluß P eines A/2-Wegeventils 5 verbunden, dessen Betätigungsglied mittels eines Gleichstrommagneten 6 betätigbar ist. Der Gleichstrommagnet 6 wird ständig mit Öl versorgt, was durch dessen Verbindung mit dem Anschluß T des Wegeventils 5 dargestellt ist.To an oil pan 1 of a drive unit, not shown, is a Pump 2 connected to its suction line 3. A pressure line 4 of the pump 2 is connected to a connection P of an A / 2-way valve 5, the actuator of which can be actuated by means of a direct current magnet 6. The DC magnet 6 is constantly supplied with oil, which is achieved by connecting it to port T of the directional control valve 5 is shown.

An die Druckleitung Lt ist eine Leitung 15 angeschlossen, die zur Anschlußstelle B des Wegeventiles 5 geführt ist. An eine Anschlußstelle A des Wegeventiles 5 ist eine Leitung 16 angeschlossen, die mit einem nach Belieben bet@tigbaren Steuerventil 17 verbunden ist, das zwei nach Belleden wählbare Ausgänge hat. Ein Ausgang des Steuerventiles 17 ist über eine Leitung 18 unmittelbar mit der Ölwanne 1 verbunden und ein anderer Ausgang über eine Leitung 19 mit einem Wärmetauscher 20, dessen Abflußleitung 21 ebenfalls zur Ölwanne 1 führt.To the pressure line Lt, a line 15 is connected to the Connection point B of the directional control valve 5 is performed. To a connection point A of the directional control valve 5, a line 16 is connected, which can be operated at will with a control valve 17 is connected, which has two outputs that can be selected according to Belleden. An output of the Control valve 17 is directly connected to oil pan 1 via a line 18 and another output via a line 19 with a heat exchanger 20, the Drain line 21 also leads to oil pan 1.

An die Druckleitung 4 ist eine Leitung 22 angeschlossen, in der sich ein vom Druck in der Druckleitung 4 gesteuertes Druckventil 23 befindet, dem eine Drosselstelle 24 nachgeschaltet ist. Die Drosselstelle 24 ist über eine Leitung 25 mit der Leitung 16 verbunden.A line 22 is connected to the pressure line 4, in which is a controlled by the pressure in the pressure line 4 pressure valve 23, the one Throttle point 24 is connected downstream. The throttle point 24 is via a line 25 connected to line 16.

Die Anschlußstelle T des Wegeventils 5 ist über eine Leitung 26 mit der Leitung 25 verbunden. Zwischen die Druckleitung 4 und die Verbindung zwischen dem Ausgang des Druckventils 23 und dem Eingang der diesem Druckventil nachgeschalteten Drosselstelle 24 ist eine das Druckventil 23 umgehende Leitung 27 eingeschaltet, in der sich eine Drosselstelle 28 befindet.The connection point T of the directional control valve 5 is via a line 26 with the line 25 connected. Between the pressure line 4 and the connection between the output of the pressure valve 23 and the input of this pressure valve downstream throttle point 24 is a line bypassing the pressure valve 23 27 turned on, in which a throttle point 28 is located.

In der in der Zeichnung dargestellten Schaltstellung des Wegeventiles 5 wird von der Pumpe 2 über das Wegeventil 5 Druckflüssigkeit (Öl) zum Steuerventil 17 gefördert, das die Leitung 16 entweder mit der Leitung 18 (Sommerbetrieb) oder mit der Leitung 19 (Winterbetrieb) verbindet. Zugleich wird über die Leitung 15, das Wegeventil 5, die Leitungen 26 und 25 ebenfalls Druckflüssigkeit von der Pumpe 2 zur Leitung 16 und damit zum Steuerventil 17 gefördert.In the switching position of the directional control valve shown in the drawing 5 is from the pump 2 via the directional control valve 5 hydraulic fluid (oil) to the control valve 17 promoted that the line 16 either with the line 18 (summer operation) or connects to line 19 (winter operation). At the same time, line 15, the directional control valve 5, the lines 26 and 25 also pressurized fluid from the pump 2 to the line 16 and thus to the control valve 17 promoted.

In der anderen Steuerlage des Wegeventiles 5 fließt Druckflüssigkeit von der Druckleitung Lt zum einen über die Leitung 27 durch die Drosselstellen 24 und 28 hindurch und über die Leitungen 25 und 16 zum Steuerventil 17 und zum anderen über die Leitung 22, das Druckventil 23 und ebenfalls durch die Drosselstelle 24 hindurch und über die Leitungen 25 und 16 zu dem Steuerventil 17. Die Drosselstelle 28 ist hierbei so gewählt, daß durch sie etwa ein Viertel der maximalen Fördermenge der Pumpe 2 hindurchfließt, wodurch das Anfahren der mit der Ölwanne 1 versehenen Antriebseinheit erleichtert wird. Die dritte Drosselstelle 28 läßt einen Strom an Druckflüssigkeit hindurchtreten, der etwa dem Strom entspricht, der zum Anfahren der Antriebseinheit notwendig ist. Die durch das Druckventl 23 hindurchtretende Druckflüssigkeit wird beim Hindurchtreten durch das Druckventil 23 erwärmt. Die dem Druckventil 23 nachgeschaltete zweite Drosselstelle 24 übt eine dämpfende Wirkung aus. Zugleich wird durch diese Drosselstelle 24 der Druck am Ausgang des Druckventiles 23 gegenüber dem Atmosphärendruck erhöht. Wegen der zweistufigen Entspannung der Druckflüssigkeit wird einem Verschäumen der aus dem Druckventil 23 austretenden Druckflüssigkeit entgegengewirkt. Die durch das Druckventil 23 hindurchgeführte und dort erwärmte Druckflüssigkeit gitt bei entsprechender Steuerlage des Stfuerventiles 17 (Winterbetrieb) im Wärmetauscher 20 ihre Wärme ab, der in einem der Antriebseinheit zugeordneten geschlossenen Raum untergebracht ist. Von der Druckleitung 4 durch das Wegeventil 5 hindurchfließende Druckflüssigkeit wird über die Leitung 15 in die Druckleitung Lt zurückgeführt. Die Leitungen 16, 25 und 26 sind kurzgeschlossen.In the other control position of the directional control valve 5, hydraulic fluid flows from the pressure line Lt on the one hand via the line 27 through the throttle points 24 and 28 through and via lines 25 and 16 to the control valve 17 and to the other via the line 22, the pressure valve 23 and also through the throttle point 24 through and via the lines 25 and 16 to the control valve 17. The throttle point 28 is chosen so that it makes about a quarter of the maximum delivery rate the pump 2 flows through, whereby the starting of the provided with the oil pan 1 Drive unit is facilitated. The third throttle point 28 starts a current Pressurized fluid to pass through, which corresponds approximately to the current required for start-up the drive unit is necessary. The passing through the pressure valve 23 Pressure fluid is heated as it passes through the pressure valve 23. the the second throttle point 24 connected downstream of the pressure valve 23 has a damping effect the end. At the same time, through this throttle point 24, the pressure at the outlet of the pressure valve is increased 23 increased compared to atmospheric pressure. Because of the two-stage relaxation of the Pressure fluid is a foaming of the emerging from the pressure valve 23 Counteracted hydraulic fluid. The passed through the pressure valve 23 and the hydraulic fluid heated there was released with the appropriate control position of the Stfuerventiles 17 (winter operation) in the heat exchanger 20 from their heat, which in one of the drive unit assigned closed space is housed. From the pressure line 4 through the directional control valve 5 flowing through pressure fluid is via the line 15 in the pressure line Lt returned. Lines 16, 25 and 26 are short-circuited.

L e e r s e i t eL e r s e i t e

Claims (2)

Ansprüche 1. Vorrichtung zum Erzeugen von Wärme in einer Druckflüssigkeit insbesondere zum Beheizen eines einer Antriebseinheit zugeordneten geschlossenen Raumes, mit einer Pumpe (2) und mit einem Druckventil (23) als wärmeerzeugende Organe, wobei die Pumpe und das Druckventil von der Druckflüssigkeit durchfließbar sind, und mit einem Wärmetauscher (20), dadurch g e k e n n z e ic h n e t , daß dem Druckventil eine Drosselstelle (24) nachgeschaltet Ist. Claims 1. Device for generating heat in a pressure fluid in particular for heating a closed one assigned to a drive unit Room, with a pump (2) and with a pressure valve (23) as heat-generating organs, whereby the pump and the pressure valve can be flowed through by the hydraulic fluid, and with a heat exchanger (20), characterized in that the pressure valve a throttle point (24) is connected downstream. 2. Vorrichtung nach Anspruch 1, dadurch g e k e n n z e i c h n e t , daß zum Druckventil (23) eine Drosselstelle (28) parallel geschaltet ist, deren Ausgang in die Verbindung zwischen dem Ausgang des Druckventils und dem Eingang der dem Druckventil nachgeschalteten Drosselstelle (24). mündet. 2. Apparatus according to claim 1, characterized in that g e k e n n z e i c h n e t that to the pressure valve (23) a throttle point (28) is connected in parallel, whose Output in the connection between the output of the pressure valve and the input the throttle point (24) downstream of the pressure valve. flows out.
DE19813141707 1981-10-21 1981-10-21 Apparatus for producing heat in a pressure fluid, in particular for heating a closed space Granted DE3141707A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19813141707 DE3141707A1 (en) 1981-10-21 1981-10-21 Apparatus for producing heat in a pressure fluid, in particular for heating a closed space

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19813141707 DE3141707A1 (en) 1981-10-21 1981-10-21 Apparatus for producing heat in a pressure fluid, in particular for heating a closed space

Publications (2)

Publication Number Publication Date
DE3141707A1 true DE3141707A1 (en) 1983-04-28
DE3141707C2 DE3141707C2 (en) 1989-02-16

Family

ID=6144534

Family Applications (1)

Application Number Title Priority Date Filing Date
DE19813141707 Granted DE3141707A1 (en) 1981-10-21 1981-10-21 Apparatus for producing heat in a pressure fluid, in particular for heating a closed space

Country Status (1)

Country Link
DE (1) DE3141707A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2150710A1 (en) * 1971-10-12 1973-04-19 Gewerk Eisenhuette Westfalia DEVICE FOR HEATING THE PRESSURE FLUID, IN PARTICULAR FLAME RESISTANT HYDRAULIC FLUIDS, FOR HYDRAULIC OPERATING SYSTEMS ETC.
DD127417A1 (en) * 1976-09-20 1977-09-21 Christoph Berndt Device for heating the pressure fluidity of hydrostatic systems
DE2943526A1 (en) * 1979-10-27 1981-05-07 Klöckner-Humboldt-Deutz AG, 5000 Köln DEVICE FOR HEATING THE PRESSURE LIQUID FOR THE WORKING HYDRAULICS OF A MOTOR VEHICLE

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2150710A1 (en) * 1971-10-12 1973-04-19 Gewerk Eisenhuette Westfalia DEVICE FOR HEATING THE PRESSURE FLUID, IN PARTICULAR FLAME RESISTANT HYDRAULIC FLUIDS, FOR HYDRAULIC OPERATING SYSTEMS ETC.
DD127417A1 (en) * 1976-09-20 1977-09-21 Christoph Berndt Device for heating the pressure fluidity of hydrostatic systems
DE2943526A1 (en) * 1979-10-27 1981-05-07 Klöckner-Humboldt-Deutz AG, 5000 Köln DEVICE FOR HEATING THE PRESSURE LIQUID FOR THE WORKING HYDRAULICS OF A MOTOR VEHICLE

Also Published As

Publication number Publication date
DE3141707C2 (en) 1989-02-16

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